Formulation Stability and Ingredient Solubility Issues

Asked by: vichai_chan On: July 22, 2022 Product Type: Cosmetics

Question

Regarding a formulation containing Ezerwax, Pure-Baicalin, Olive Oil PEG-7 Esters, and other ingredients, I would like to know if Ezerwax and Pure-Baicalin are soluble in Olive Oil PEG-7 Esters, and if Olive Oil PEG-7 Esters is sufficient to emulsify the oil phase to achieve a stable formula.

Answer

Formulation Review

Based on the ingredients provided in your formula:

  1. Solubility of Ezerwax and Pure-Baicalin in Olive Oil PEG-7 Esters:

    • Ezerwax is an oil-soluble ingredient (a wax blend). Olive Oil PEG-7 Esters is a water-soluble emollient/solubilizer. Therefore, Ezerwax will not dissolve in Olive Oil PEG-7 Esters.
    • Pure-Baicalin is a water-soluble extract. It will dissolve in the water phase of your formula, where Olive Oil PEG-7 Esters is also soluble. However, Pure-Baicalin does not dissolve directly in Olive Oil PEG-7 Esters itself.
  2. Emulsification Stability using Olive Oil PEG-7 Esters:

    • Olive Oil PEG-7 Esters is primarily designed as a water-soluble emollient or solubilizer for incorporating small amounts of oils or fragrances into water-based systems like toners or cleansing waters. It is generally not a sufficient emulsifier to create a stable emulsion (like a cream or lotion) with a significant oil phase.
    • Your formula includes 5% Ezerwax (an oil-soluble wax) and 5% Olive Oil PEG-7 Esters. Relying solely on Olive Oil PEG-7 Esters to emulsify this amount of oil-soluble material will likely result in stability issues and separation of the water and oil phases over time.

To achieve a stable emulsion, you would typically need to include a proper emulsifier system designed for your specific oil phase percentage and desired product type (e.g., a non-ionic emulsifier blend for an oil-in-water emulsion).